Colorectal cancer generally is a cancer from uncontrolled cell growth in the colon or rectum (parts of the large intestine) or in the appendix. Genetic analyses shows that essentially colon and rectal tumors are genetically the same cancer (see, e.g., Cancer Genome Atlas Network (19 Jul. 2012) Nature 487 (7407)). Symptoms of colorectal cancer typically include rectal bleeding and anemia which are sometimes associated with weight loss and changes in bowel habits.
Diagnosis of colorectal cancer is via tumor biopsy typically done during colonoscopy or sigmoidoscopy, depending on the location of the lesion. The extent of the disease is then usually determined by a CT scan of the chest, abdomen and pelvis. There are other potential imaging test such as PET and MRI which may be used in certain cases. Colon cancer staging is done next and based on the TMN system which is determined by how much the initial tumor has spread, if and where lymph nodes are involved, and if and how many metastases there are (see, e.g., Cunningham D, et al. (2010) Lancet 375 (9719): 1030-47).
At least 50% of the Western population will develop a colorectal tumor by age 70 years. In 10% of these individuals, the tumor progresses to malignancy. In adults, colorectal cancer is the second leading cancer that causes death worldwide (see, e.g., Bi X, et al., (2006) Mol Cell Proteomics 5(6):1119-30).
As such, improved techniques for detecting, treating and understanding colorectal cancer are needed.